Process of concentrating and purifying sludge-acid.



' APPLICATION FILED JULY 19. 1909.

Patented Apr. 26, 1910.

WITNESSES @5001 W11 Es LEQI POLD BLACHER AND -STANISI IAUS SZTENGEL, OFCAJMPINA, ROUMANIA.

PROCESS OF C ONCENTRATING AND PURIFYING SLUZDGE-ACID.

Specification of Letters Patent.

Application filed July 19, 1909. Serial No. 508,325.

To all whom it may concern:

Be it known that we, LEOPOLD BLACHER, manager,-a subject of the Emperor of Russia, and S ANIsLAUs SZTENCEL, engineer, a subject of the Emperor of Austria-Hungary, residing at Campina, Roumania, have invented certain new and useful Improvements in Processes of Concentrating and Purifying Sludge-Acid; and we do hereby declare the following to be a full, clear, and exact clei scription of the invention, such as will en- I sectional side elevatlon of one form of apparatus employed in carrying out the imable othersskilled in the art to which it appertains to make and use the same.

The waste acid resulting from the purification of mineral oils, which has been re-;

generated in the usual manner by addition of water, still contains up to 2.5% organic substances of complicated nature, which ive to the acid a dark color. This black-acid is a product of little value, as it cannot be used for man purposes, and even in the purification o mineral oils it is not equivaent to pure acid. The impurities contained in the acid may be partly destroyed by heating, the organic substances being totally decomposed at a higher temperature, and separating from the acid in form of asphalt or graphite. Till now however, it has not been possible to purify the acid altogether by heating alone. We have now found, that by treating the acid to the oxidizing action of air, the organic substances may be easily converted into carbonic acid and eliminated. This discovery is utilized for'the regeneration of black acid by the present process.

The accompanying drawing represents a proved process.

According to the present process pure concentrated sulfuric acid is heated to boiling point in a suitable boiler a, and the blac v acid run in continuously from the vessel 6 through lown by means of the pipe 03 into the mixed acids contained in the boiler a.

Practically pure sulfuric acid distils over through pipe e and is condensed by the condenser f, in which water enters through pipe 9 and flows out through the outlet. 12.. The condensed acid is collected in the vessel z from which it may bewithdrawn by ipe in. Z is a pipe through which the air and other gases escape.

The quantity of black acid run in in a given time is so regulated, that the temperature in the boiler remains constant at substantially the boiling point of sulfuric acid.

Fromthis point the process may be carried I Our process may be carried outeither with the diluted black acid directly, or after previously concentrating it in the usual manner. In case diluted acid is used,the oxidized acid may be concentrated after condensation.

We claim Patented Apr. 26, 1910.

The process herein described of obtaining practically pure sulfuric acid from sludge acid, consistin in running the waste acld into a suitab e. boiler containing concentrated sulfuric acid heated to boiling point, blowing a current of air through said acid, and condensing the vapors escaping from the boiler by the usual means.- I I In testimony, that we claim the foregoing as our invention, we have signed our names in presence of two subscribing witnesses.

LEOPOLD BLACHER. STANISLAUS SZTENCEL. Witnesses:

GERHARD BERGER, 

